'\" te
.\" Copyright (C) 2008, Sun Microsystems, Inc. All Rights Reserved.
.\" The contents of this file are subject to the terms of the Common Development and Distribution License (the "License").  You may not use this file except in compliance with the License.
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.TH NET_ISPARTIALCHECKSUM 9F "May 1, 2008"
.SH NAME
net_ispartialchecksum \- indicate if a packet is being scheduled for hardware
checksum calculation
.SH SYNOPSIS
.nf
#include <sys/neti.h>

\fBint\fR \fBnet_ispartialchecksum\fR(\fBconst\fR \fBnet_data_t\fR \fInet\fR, \fBmblk_t\fR *\fImb\fR);
.fi

.SH INTERFACE LEVEL
illumos DDI specific (illumos DDI).
.SH PARAMETERS
.ne 2
.na
\fB\fInet\fR\fR
.ad
.RS 7n
value returned from a successful call to \fBnet_protocol_lookup\fR(9F).
.RE

.sp
.ne 2
.na
\fB\fImb\fR\fR
.ad
.RS 6n
the \fBmblk\fR structure holding a packet that is the subject of this query.
.RE

.SH DESCRIPTION
The \fBnet_ispartialchecksum()\fR function looks at the fields within the
\fBmblk\fR structure to determine if the packet contained inside contains
headers with only partial checksum values. Partial checksum values are stored
inside headers when the calculation of the complete checksum is being handled
by the hardware.
.SH RETURN VALUES
The \fBnet_ispartialchecksum()\fR function returns:
.sp
.ne 2
.na
\fB-1\fR
.ad
.RS 6n
The network protocol does not support this function.
.RE

.sp
.ne 2
.na
\fB0\fR
.ad
.RS 6n
The packet does not contain partial checksums.
.RE

.sp
.LP
If a packet is marked for hardware checksum'ing, the following values are
returned:
.sp
.ne 2
.na
\fB\fBNET_HCK_L3_FULL\fR\fR
.ad
.RS 19n
Complete layer 3 checksum calculated
.RE

.sp
.ne 2
.na
\fB\fBNET_HCK_L3_PART\fR\fR
.ad
.RS 19n
Partial layer 3 checksum calculated
.RE

.sp
.ne 2
.na
\fB\fBNET_HCK_L4_FULL\fR\fR
.ad
.RS 19n
Complete layer 4 checksum calculated
.RE

.sp
.ne 2
.na
\fB\fBNET_HCK_L4_PART\fR\fR
.ad
.RS 19n
Partial layer 4 checksum calculated
.RE

.SH CONTEXT
The \fBnet_ispartialchecksum()\fR function may be called from user,  kernel, or
interrupt context.
.SH ATTRIBUTES
See \fBattributes\fR(7) for descriptions of the following attributes:
.sp

.sp
.TS
box;
c | c
l | l .
ATTRIBUTE TYPE	ATTRIBUTE VALUE
_
Interface Stability	Committed
.TE

.SH SEE ALSO
.BR attributes (7),
.BR net_isvalidchecksum (9F),
.BR net_protocol_lookup (9F)
